The present invention is related to a granulated bread improver for the preparation of bakery products, and to the bakery products comprising said improver.
The present invention is also related to the preparation process of said granulated bread improver.
Baked bread products are made of the basic ingredients: flour (mostly wheat or rye flour), water, salt and yeast. Other types of flour (barley, oats, soy, sunflower, cassava and. other). The process of baking is subject to a lot of variations due to external (temperature, humidity, handling) and internal (variations of flour and yeast quality) factors.
To obtain a more reliable production process and a constant end product the baker uses ingredients and additives. These products are mostly added as one coformulated product and are known as improvers. These improvers may contain emulsifiers and fats, enzymes, sugars, organic acids, minerals, polysaccharides and proteins. This includes products such as diacetyltartaric acid esters of monoglycerides, lactic acid ester of monoglycerides, monoglycerides, amylases, hemicellulases and pentosanases, oxidases, lipases, proteinases, glucose, fructose, sucrose, ascorbic acid, lactic acid, phosphates, sulphates, guar, locust bean gum, gluten, soy proteins.
Said list is not exhaustive and is presented as an illustration of a possible improver. A mixture of ingredients active in the preparation process of baked goods is called an improver as soon as it contains more than one class of active components mixed together as to optimise by a synergetic effect their performances in the baking process. The mixing of several enzymes does not lead to obtain an improver. On the other hand, mixing one or more enzymes with an emulsifier (for example DATEM) or with ascorbic acid gives the formulation of an improver.
The improver can be formulated as a liquid, as a paste or more commonly as a powder. The powdered formulation contains the active ingredients as above-mentioned and a carrier substance. The carrier substance is added to the active ingredients in order to dilute them to the suitable concentration. The improver will be added by the baker in a concentration of 0.5 to 20% to the flour.
The most currently used carrier substances are starch, wheat flour or soy flour. The powdered formulation of the improver is very stable, and easy to weigh and to store.
However, said formulation presents also various drawbacks. If one of the components is an emulsifier or another fat-based product, the improver will tend to stick, which may result in more or less compact lumps.
This effect is more pronounced at higher temperatures. As a result of its poor free flowing characteristics, the improver is not easily carried by automatic dosing systems and tends to get stuck in the pipes. This also makes dosing inaccurate, and makes the cleaning of the pipes arduous. In addition, a flour which contains a lot of small particles may give rise to allergic reactions for sensitised persons, for instance as in baker""s disease which is well known to be caused by allergenic wheat flour particles and by the powdered additives.
In various fields, it has been proposed to increase the particle size of various compositions.
The enzyme producers have granulated their enzymes to reduce this risk of allergenicity as illustrated in the U.S. Pat. No. 4,940,665.
The International Patent Application WO93/07260 describes the manufacturing of dust free particles of enzymes by spray-coating solid particulate cores.
The European Patent Application EP-A-0289069 describes also oil or fat obtained in a granular form.
The European Patent Application EP-A-0659344 describes a dry yeast composition consisting of dry inactive yeast and a bread improving agent which is preferably in a granular form or consists of small particles adhering larger yeast granules. This European Patent Application also describes a process to obtain a mixture of hemicellulase, amylase and Vitamin C in a granular form.
One might try to overcome the disadvantages of a powder form improver by applying the teaching of the European Patent Application EP-A-0659344 and thus producing or buying granulated ingredients or mixtures of ingredients. This however will result in a non-homogeneous particle distribution. In the specific applications described in the European Patent Application EP-A-0659344, said drawbacks are not important, because the end product is packed under reduced pressure afterwards, becomes a firm block and the particles are not able to move relative to one other. Mixing all improver ingredients in one solution and granulating as described in the European Patent Application EP-A-0659344 will only be efficient if all ingredients are miscible and stable in water. This is mostly not the case for bread improvers. This is illustrated by the fact that common emulsifiers as diacetyltartaric ester of monoglycerides or stearoyllactylates are readily hydrolysed in water and can not be used in aqueous solutions. It is also impossible to make aqueous solutions incorporating enzymes when at least one protease is to be present in the mixture.
The main aim of the invention is to provide a bread improver in the form of a powder and its preparation process which do not present the drawbacks of the above-mentioned state of the art.
The main aim of the invention is to provide a bread improver in the form of a powder and its preparation process, which presents improved free-flowing properties, which is more easy to handle and which may reduce the risk of potential allergenicity.
The present invention is related to a bread improver in the form of a powder which is made of agglomerated particles having a mean particle size of at least 250 xcexcm. The mean agglomerated particle size of this product is preferably comprised between 300 and 2000 xcexcm.
Preferably, the standard deviation/mean agglomerated particle size ratio is lower than 0.8, preferably lower than 0.65.
In a preferred embodiment of the present invention, the particles are made of at least 2 different active ingredients, advantageously balanced to obtain an effect in bakery products.
The improver according to the invention can further comprise one or more ingredients selected from the group consisting of emulsifiers, fats, enzymes, sugars, organic acids, minerals, polysaccharides, proteins and/or a mixture thereof.
A second aspect of the present invention is related to a method for obtaining the granulated improver in the form of a powder according to the invention, said method comprising the steps of:
preparing a starting material being a bread improver in the form of a dried powder having a mean particle size lower than 200 xcexcm,
introducing and maintaining said starting material in a fluidised bed reactor, under spraying of an atomised liquid, in order to obtain an agglomeration of the dried powder particles of said material, and
recovering a bread improver in the form of a dried powder made of agglomerated particles having mean particle size of at least 250 xcexcm.
In the method according to the invention, the standard deviation/mean agglomerated particle size ratio of the agglomerated particles is preferably lower than the standard deviation/mean agglomerated particle size ratio of said starting material.
In the method according to the invention, said liquid comprises water and preferably further comprises an agglomerating agent selected from the group consisting of polysaccharides (such as guar, alginate, carrageenan, pectin, maltodextrins) or proteins (such as gelatin) and/or a mixture thereof.
In the method according to the invention, the temperature of the fluidised bed reactor is preferably comprised between 20 and 45xc2x0 C., more preferably between 25 and 40xc2x0 C.
Advantageously, the fluidised bed reactor used in the method according to the invention is a Glatt granulating device. However, other fluidised bed equipments are also suitable for the preparation of the bread improver according to the invention. Examples are Allgaier Wirbelschichttrockner (Allgaier Uhingen, GERMANY) and Vector Fluid Bed (Vector Marion, Iowa, USA).